/*
 * Copyright (c) 2010 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package com.google.api.client.json;

import com.google.api.client.http.HttpContent;

import org.codehaus.jackson.JsonEncoding;
import org.codehaus.jackson.JsonGenerator;

import java.io.IOException;
import java.io.OutputStream;

/**
 * Serializes JSON HTTP content based on the data key/value mapping object for an item.
 * <p>
 * Sample usage:
 *
 * <pre>
 * <code>
 * static void setContent(HttpRequest request, Object data) {
 *   JsonHttpContent content = new JsonHttpContent();
 *   content.data = data;
 *   request.content = content;
 * }
 * </code>
 * </pre>
 *
 * @since 1.0
 * @author Yaniv Inbar
 */
public class JsonHttpContent implements HttpContent {
  // TODO: ability to annotate fields as only needed for POST?

  /** Content type. Default value is {@link Json#CONTENT_TYPE}. */
  public String contentType = Json.CONTENT_TYPE;

  /** Key/value pair data. */
  public Object data;

  public long getLength() {
    // TODO
    return -1;
  }

  public final String getEncoding() {
    return null;
  }

  public String getType() {
    return Json.CONTENT_TYPE;
  }

  public void writeTo(OutputStream out) throws IOException {
    JsonGenerator generator = Json.JSON_FACTORY.createJsonGenerator(out, JsonEncoding.UTF8);
    Json.serialize(generator, data);
    generator.close();
  }
}
